Locked corner box and blank



Oct. 23, 1962 P. THOMPSON LOCKED CORNER BOX AND BLANK 2 Sheets-Sheet 1Filed April 15, 1959 Fig. 1

Fig. 2

mmvroa Paul Thompson A T TORNE Y Oct. 23, 1962 P. THOMPSON LOCKED CORNERBOX AND BLANK 2 Sheets-Sheet 2 Filed April 15, 1959 Fig. 4

Fig. 5

INVENTOR. Paul Thompson JW ZJWMZM A 1' T qkIvEr 3,059,829 Patented Oct.23, 1962 3,059,829 LOCKED CORNER BOX AND BLANK Paul Thompson, 15Tennyson Road, Wellesley Hills, Mass. Filed Apr. 15, 1959, Ser. No.806,525 4 Claims. (Cl. 229-35) This invention relates to foldedpaperboard boxes of the locked corner type wherein adjacent side wallsof the box are interlocked through slits to support the walls in uprightposition. Each such box is formed from a scored blank which blanks areordinarily shipped flat to the consumer and need to be set up as used,such operation requiring considerable time and/ or setting up mechanism.My invention herein contemplates a blank and box of this nature which ispartially set up at the manufacturing plant and shipped therefrom to theconsumer in compact nested relation. The construction is such that theconsumer needs only to press the ends of the nesting box together tocomplete the setting up operation, thus facilitating rapid use of thebox without the aid of expensive setting up machinery.

The invention particularly concerns a novel corner lock wherein a flapintegral with a side panel at each corner is adapted to fold to cornerforming relation overlapping the adjacent panel and interlockingtherewith through a slit herein. The relation at the slit is such thatthe flap carrying panels can be folded either to full and upright cornerforming relation with the adjacent panels or to a partially foldedposition inclined outwardly therefrom. In the latter position the boxesare adapted to be nested in compact relation for easy and convenientshipping and each box can be brought to fully set up position mereby bypressing the flap carrying panels toward each other. The production of abox of this nature having corner locks as and for the purpose describedcomprises the primary object of the invention.

These and other features of the invention will be more readilyunderstood and appreciated from the following detailed description ofpreferred embodiments thereof, selected for purposes of illustration andshown in the accompanying drawings, in which- FIG. 1 is a fragmentaryview of a box blank embodying the invention,

FIG. 2 is a fragmentary view of the blank folded to nesting and shippingposition,

FIG. 3 illustrates the blank fully folded to box form,

FIG. 4 illustrates a stack of partially folded boxes in nested relation,

FIG. 5 is a fragmentary view of a modified form of blank,

FIG. 6 illustrates this blank folded to box form, and

FIG. 7 is a plan view of this blank partially folded for nesting.

The paperboard blank 10 illustrated in FIG. 1 is scored on lines 12 and14 to provide a bottom panel 16 and side wall panels 18 and 20. A cornerforming flap 22 is integral with one end of the panel along a score line24 and is provided with a locking ear 26 at its outer margin.

Each end of the panels 18 is slitted at 28 to receive the adjacentlocking ear 26 therethrough when the panels are folded upwardly asillustrated in FIG. 2. The panels 18 are also provided with slits 30spaced from the slits 28. Each locking ear 26 includes a tip end portion32 disposed to overlap the panel 18 when the shoulder 34 of the ear isin contact with a marginal edge of either slits 28 or 30. When theshoulder is engaged with the marginal edge of slit 30 the panel 20 isinclined outwardly as illustrated in FIG. 2 and when the panel 20 ismoved inwardly to the position of FIG. 3 the shoulders 34 engage themarginal edges of the slits 28 and support the panels 20 in the fullyupright and full corner forming relation illustrated. The tip end 32 ofthe locking ear is slightly bent forward (FIG. 1) to facilitate itspassage through the slit and the engagement. of the shoulder 34 with theslit margins. The panel 18 is also preferably provided with a slit 36converging into the slit 30 and forming a wing 38 adapted to aid insupporting and facilitating the operation of the locking ear.

In FIGS. 5, 6 and 7 I have illustrated a modified construction in whichparts corresponding to those of FIGS. 1-3 are indicated by likereference characters primed. In this construction the locking ear 26 ofthe flap 22' is provided with two shoulders 40 and 42 for engaging amarginal edge of the slit 28' as illustrated in FIG. 6. When theshoulders 40 are thus engaged the panels 20' are supported in theoutwardly inclined position illustrated in FIG. 7 and in broken lines inFIG. 6 and when the shoulders 42 are thus engaged the panels are foldedin the fully upright and full corner forming .relation illustrated infull lines in FIG. 6.

The flat blanks are folded at the manufacturing plant to the nestingrelation shown in FIGS. 2, 4 and 7 and are shipped to the consumer inthe compact nested relation illustrated in FIG. 4. The consumer hasmerely to push the end panels 20 inwardly to the fully upright positionand the box is ready for use. Thus no setting up machinery is requiredand the operation is quick and economical. Particular attention iscalled to FIG. 7 wherein is illustrated not only the outwardly inclinedposition of the panels 20' but also the outwardly inclined bowing of thepanels '18 whereby each partially folded blank quite naturally nestscompletely with the adjacent blanks. Attention is also called to theslight bend on the tip 32 of each locking car which facilitates theautomatic locking engagement. My improved box has no weakening diagonalfolds at the corners, uses a minimum of paper stock, is conveniently andeconomically shipped in nested relation and can be set up quickly andeconomically without the employment of expensive mecha nism.

Having thus disclosed by invention, what I claim as new and desire tosecure by Letters Patent is:

1. In a paperboard box embodying a rectangular bottom panel and fourside wall panels folded upwardly therefrom to provide side walls forminga box corner at the junction of each two adjacent side panels, a cornerlock at each corner of the box comprising a flap integral with one endof a side panel and folded right angularly thereto to provide a cornerwall overlapping the adjacent side panel, said adjacent side panel beingslitted therethrough adjacent to said corner wall, and interlockingmeans including a locking ear integral with the flap and extendingthrough said slitted panel and including coabutting stop shoulders onthe locking ear and said slitted panel for optionally and positivelysupporting said side panel folded either in upright and full cornerforming relation with said adjacent panel or inclined outwardlytherefrom, the box being adapted to nest compactly with other like boxeswhen its corners are supported in the outwardly inclined position.

2. The corner lock defined in claim 1 in which said interlocking meansincludes two spaced shoulders on said ear disposed to engage a marginaledge of said adjacent panel at the slit therethrough for supporting saidside panel in said upright and outwardly inclined positionsrespectively.

3. The corner lock defined in claim 1 in which said interlocking meansincludes a stop shoulder on said ear disposed to engage a marginal edgeof said adjacent panel at one slit therethrough for supporting said sidepanel in upright position and to engage another marginal edge of saidadjacent panel at another and relatively spaced slit for supporting saidside panel in the outwardly inclined position.

4. The corner lock defined in claim 3 in which said ear includes a tipend portion integral therewith beyond said shoulder for overlapping saidside panel at said slits when the shoulder is engaged with said marginaledges at the slits, said tip end portion of the ear being bent laterallyout of the plane of the ear to facilitate engagement of said shoulderwith the marginal edges.

UNITED STATES PATENTS Ramsey Ian. 17, 1905 Higginson July 17, 1923Metcalf Dec. 14, 1943 Trickett et al. Nov. 24, 1953 FOREIGN PATENTSGermany May 1, 1906 Great Britain July 27, 1955

